N.Y. Firefighter Shooting Update: Body found in home of gunman William Spengler

(CBS/AP) WEBSTER, N.Y. -- Police have found a body inside the charred remains of the home of the New York man who police say shot and killed two firefighters and injured two more early on Christmas Eve.

PICTURES: Cops: N.Y. ex-con gunned down firefighters

William Spengler, 62, who served 17 years in prison for manslaughter in the 1980 hammer slaying of his grandmother, set his house afire before dawn on Dec. 24, before taking a revolver, a shotgun and a semiautomatic rifle to a sniper position outside, Police Chief Gerald Pickering said.

Police revealed that a body believed to be the killer's 67-year-old sister, Cheryl Spengler, was found in his fire-ravaged home.

Authorities say Spengler sprayed bullets at the first responders, killing two firefighters and injuring two others who remained hospitalized Tuesday in stable condition, awake and alert and expected to survive. He then killed himself as seven houses burned on a sliver of land along Lake Ontario.

Pickering said it was unclear whether the person believed to be Spengler's sister died before or during the fire.

"It was a raging inferno in there," Pickering said.

A next-door neighbor said Spengler hated his sister and they lived on opposite sides of the house.

Roger Vercruysse said Spengler loved his mother, Arline, who died in October after living with her son and daughter in the house in a neighborhood of seasonal and year-round homes across the road from a lakeshore popular with recreational boaters.

Complete coverage of the Webster firefighter shooting on Crimesider